Abstract: In a process for hydroponic cultivation of plants an irrigation solution containing water and at least one nutrient is circulated through a main loop at a first point where a disinfectant is added to the irrigation solution. At a second point at least one nutrient is added to the irrigation solution. At a third point the plants are supplied with the irrigation solution, and at a fourth point the irrigation solution drained of the plants is collected. The main loop is provided with one or more sub-loops through which the irrigation solution is recirculated.

Abstract: Solutions of sugars obtained during the processing of foodstuffs can be subject to bacterial contamination. In view of the possible legislation to prevent the use of existing disinfectants such as formaldehyde in these conditions, alternative treatments are needed. Effective disinfection of sugar solutions can be achieved employing a peracetic acid solution containing a high mole ratio of hydrogen peroxide to peracetic acid, such as from 18:1 to about 54:1 in combination with a second peracetic acid solution.